Taylor28

I have read countless threads on sound deadening for XJs but can't seem to get a comprehensive approach. I have removed the headliner and fully insulated the roof, then removing the draping headliner material and used bedliner in its place. (Photo attached) There was a slight improvement in noise but it's still pretty loud--especially at higher speeds.
I purchased some fatmat to insulate the floorboards but before I go through all that trouble, I want to make sure I am pursuing the right process. Does it make more of a difference to do both bedliner AND fatmat? How many layers of fatmat?
I basically just want to be able to have a phone conversation where I can actually hear the other person and not feel like I'm shouting.

andrewmp6

Bed liner has no sound deaden in it so yeah it would be better to use sound deaden on the floors the roof and i have put it inside car doors before.

by921

You may be better off putting some kind of foam on the floor as it is better at absorbing noise than a mass loading product.

investinwaffles

I went with Frost King mostly to insulate the floor boards, wasn't really thinking about noise (just tired of cooking in the summer time). Worked great for cutting down on heat from the trans tunnel (carpet was probably 150-160*F before, now it is barely above the regular ambient temp of the interior).

It did cut down on noise significantly, so much so that I am actually now going to do the doors with FatMat or Dynamat, and probably parts of the roof (but I have headliner).

EDIT:
Don't use FrostKing or any of those duct insulation wrap for anything other than the floor. Doesn't stick worth a crap

mschi772

See www.sounddeadenershowdown.com for the most comprehensive approach to sound deadening automobiles. Don Sambrook is to sound as Daniel Stern is to lighting.

Bed liner does nothing.

Dynamat/Fatmat/asphalt peel and seal/CLD/Second Skin in layers is a TREMENDOUS waste of money. That is NOT what those products are for.

Taylor28

I watched a youtube video on the application of a floorboard coating that looked a bit like bedliner. The poster referenced it's affect on the sound inside the Jeep. It seemed like it couldn't have too much of an impact - but I figured that while I had all the carpets out, I might as well do it. My other thought was that it would help mitigate any future rust issues. I don't have any rust issues currently -- even after living right on the beach for 4 years.

Taylor28

Thanks -- I'll look into Frost King. Surprisingly my Jeep seems to stay pretty cool -- even in the SC heat. But, I'm sure that I've just adjusted to the reality of having an old Jeep. Wouldn't mind some more insulation for temps as well -- will likely allow my AC to work a bit more efficiently in the Spring/Summer.

Taylor28

Thanks so much for the link! Best info I've seen yet. Everything I had read up until this point had recommended fatmat/dynamat, etc.

JSJJ388

I bedlinered my roof for a headliner and could definatly tell a difference between bare metal. But it is louder than with the actual headliner in it. IMO if youve got the carpet up its not a bad idea.

andrewmp6

If you want something spray on http://www.lizardskin.com/